Fix default perm for apt_repo files. (#4072)
Fix default perm for apt_repo files. (#4072)

Change the file mode arg to 'raw' ala file args

Following the file_common_args model, change the
type of the 'mode' arg here to type='raw' with no
default arg value.

The default mode for file creation is the module
constant DEFAULT_SOURCES_PER, and is used if no
mode os specified.

A default mode of 0644 (and not specified as int or str)
would get converted to an octal 420, resulting in the
sources file being created with mode '0420' instead of '0644'

Fixes #16370

thaim/ansible,thaim/ansible